Washington, United Nations call for an immediate truce as Gaza toll tops 500

GAZA CITY, Palestinian Territories -- Washington and the United Nations demanded an "immediate cease-fire" in Gaza on Monday as Israel pressed a blistering assault on the enclave, pushing the Palestinian death toll to 514.

As world efforts to end the fighting gathered pace, Israel said it killed 10 Hamas militants in an early morning gun battle after they entered southern Israel through cross-border tunnels.

At an urgent meeting on Gaza, the U.N. Security Council urged an "immediate cessation of hostilities" in a call echoed by U.S. President Barack Obama in a telephone conversation with Israeli Prime Minister Benjamin Netanyahu.

With growing concern over the number of civilian deaths, both U.S. Secretary of State John Kerry and U.N. chief Ban Ki-moon headed to Cairo for cease-fire talks, which have so far been rejected by the Islamist Hamas movement.

Following the deadliest day in Gaza in more than five years, in which at least 140 Palestinians were killed, medics pulled another 45 bodies from the rubble early Monday, emergency services spokesman Ashraf al-Qudra said.

And 20 more people were killed in a series of strikes across Gaza.

In the latest incident, tank-shelling on a hospital in Deir al-Balah in central Gaza killed five people.

And a family of nine was killed in the southern city of Rafah, seven of them children, he said.

As the diplomatic efforts gathered steam, hundreds of people could be seen flooding out of the northern town of Beit Hanun, a day after many thousands fled an intensive Israeli bombardment of the eastern district of Shijaiyah.

On Sunday, at least 72 people were killed in Shijaiyah during a punishing Israeli operation which reduced much of the district to rubble and left charred bodies lying in the streets.